A plasma display panel (hereinafter referred to simply as “PDP”) has drawn attention recently as a display panel excellent in visibility. The PDP can be grouped into AC-driven PDP and DC-driven PDP from the viewpoint of a driving method, or surface-discharge PDP and opposed-discharge PDP from the viewpoint of a discharge method. However, the present growing trend of higher resolution, larger screen and simpler fabrication makes the AC-driven and surface discharge PDP go mainstream.
The AC-driven and surface-discharge PDP comprises the following elements:
a front plate including plural display electrodes formed of scan electrodes and sustain electrodes; and
a back plate including plural data electrodes.
The front plate confronts the back plate with barrier ribs in between such that the display electrodes intersect with the data electrodes at right angles and a discharge space is formed therein. Discharge cells (a unit of emitting area) are formed at respective intersections of display electrodes and the data electrodes, and each one of the discharge cells includes a phosphor layer.
Application of a voltage between the display electrodes and the data electrodes generates discharge, and the phosphor layer is irradiated with ultraviolet rays resulting from the discharge, thereby producing visible light, which results in displaying a video.
In the steps of manufacturing the foregoing PDP, there is an exhaust-baking step for exhausting impurity gas outside a PDP. To be more specific, while a PDP is heated, the PDP is exhausted of air via an exhausting hole which is disposed on the back plate and communicates with the inside of the PDP. After this step, the discharge cells are filled with discharge gas. This procedure is disclosed at, e.g. pages 79-80, and pages 102-105 of “Everything about PDP” written by Messrs. Hiraki Uchiike and Shigeo Mikoshiba, and published from Industry Investigation Inc. on May 1, 1997.
A degasser (getter), i.e. gas adsorption member, is disposed in the vicinity of the exhausting hole for exhausting the PDP of air to a higher degree of vacuum in a shorter time, and the exhaust-baking step with the degasser results in more effective exhaust. In such a case, the degasser is placed in a space formed between the back plate and a pedestal of an exhausting pipe surrounding the exhausting hole. When the exhaust-backing step is carried out in the foregoing structure, the exhausting hole can be closed or clog with the degasser depending on a location of the degasser. As a result, the exhaust sometimes does not work functionally.
In case of such a trouble, the manufacturing operation of PDP must be temporarily halted, which causes an operation loss or reduces the yield because PDPs having insufficient degassing effect are produced.
The present invention addresses the problems discussed above, and aims to provide PDPs equipped with a degasser producing sufficient gas adsorption effort and free from problems at the exhaust-baking step.